C0139 Diagnostic Trouble Code

C0139 is a kind of OBD-II Diagnostic C-Chassis Diagnostic Trouble Code.

It is considered generic because it applies to all makes and models of vehicles, although specific repair steps may be different depending on your car model.

Symptoms

Symptoms of a C0139 diagnostic trouble code may include:

Rich or lean exhaust
Fuel pressure too low
Engine surge
The light may stay on or light intermittently as the DPF regenerates. The engine will be sluggish on acceleration.

Possible Causes :

An air leak forward of the DPF will change the sensor readings resulting in the code
Rusty exhaust systems, cracked exhaust manifolds or damaged or missing gaskets or donuts will cause air leaks.
Faulty IMRC actuator relay (if equipped)

Repair Processes :

Use the DVOM to test resistance and continuity on all system circuits if actuator and sensor resistance levels are in compliance with manufacturer's specifications. With the valve disconnected, the red voltmeter lead should be attached to the IMRC valve power wire and the black voltmeter lead connected to ground. Replace the oxygen sensor that is downstream from the catalytic converter on the side of the engine that does not contain cylinder #1. Also, if a oxygen sensor code stating "heater circuit malfunction" the sensor has most probably failed.

Process Tips

Diagnostic trouble code C0139 is not difficult to diagnose and repair. Thus, it always pays to have a qualified technician to look after your vehicle should this error code arise.

Diagnosing this code requires the engine to be in good running shape, without unmetered air entering the engine. If other codes that relates to misfiring condition, lean running or air entering the engine is present, then you must first fix those error codes before C0139.

Fortunately, C0139 is a fairly common OBD code, meaning that it applies to all makes and models of vehicles made after 1996.

C0139 Trouble Code For Specific Cars

C0139 Alfa Romeo 149 ABS Outlet Valve Coil RR Circuit Failure
C0139 Citroen 12 Fan Secondary High With Fan(s) Off
C0139 Pontiac G6 Exhaust Valve Control Solenoid Circuit (Bank 1)
C0139 Lancia Thesis Starter Disable Circuit
C0139 Alvis Ta Air Flow Recirculation Door Driver Circuit Failure
C0139 Adams 16 ABS Inlet Valve Coil Rear Circuit Short To Ground
C0139 Pontiac Grand Prix Exhaust Valve Control Solenoid Circuit Range/Performance (Bank 1)